Currently, real time PRI correlation is accomplished by matching thresholded pulses together on a pulse by pulse basis. This type of correlation requires that the pulses already be thresholded and be at a Signal-to-Noise Ratio (SNR) sufficiently high such that the false alarm rate will be within the system requirement levels. Also, these prior art types of correlators do not provide any signal-to-noise ratio gain as part of their operation. The signal-to-noise ratio remains constant or deteriorates.
In the performance of spectral analysis of signals which are pulse modulated, it is desirable to determine characteristics related to the signals, these characteristics including PRI, PW, staggers and stagger positions. Other desirable features of a PRI correlator include ability to operate at low SNRs and ability to reject signals which are not matched to the selected correlator. It is therefore apparent that a system which is capable of collecting pulse information at lower than normal prior art signal-to-noise ratios is highly desirable.